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Abstract Carbon-doped silicon oxide (CDO) thin films as low dielectric constant materials were deposited on both n-type silicon (Si) (100) and indium tin oxide coated polyethylene naphthalate (ITO/PEN) substrates, using the plasma-enhanced chemical vapor deposition of tetrakis(trimethylsilyoxy)silane (TTMSS) precursor. Chemical structures of the CDO films were analyzed by using FTIR (Fourier transformation infrared) spectroscopy and XPS (X-ray photoelectron spectroscopy). The chemical bonds related with hydrocarbon and Si–O were the main characteristics of the CDO films. The prominent peaks from the FTIR spectra included Si–O–Si stretching, Si–CH3 bending, Si–(CH3)x stretching, and CHx stretching modes. XPS spectra composed of the O1s, C1s, and Si2p electron orbitals were used to quantitatively analyze the elemental composition of the CDO films. The growth mechanisms of CDO films were dependent on the substrate type. For the ITO/PEN substrate, the lack of Si atoms on the ITO surface made difficulty in forming initial Si–O bonds, resulting in insufficient Si–O–Si structure. In comparison, the CDO films could grow easily on Si substrates due to pre-existing Si–O bonds on the surface. The chemical structures of the CDO films are expected to affect electrical and mechanical performances.
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This content will become publicly available on March 1, 2026
Carbon impurities in oxide thin films: The effect of annealing and laser irradiation
Carbon is a common contaminant in oxide thin film semiconductors that can affect important properties such as the work function, surface chemistry, and electrical conductivity. In this work, carbon impurities in sputtered anatase titania (TiO2) and indium tin oxide (ITO) thin films were investigated using Raman and optical transmission spectroscopy. Annealing in a rough vacuum yielded carbon precipitates, which have characteristic disordered and graphitic carbon Raman signatures. Irradiation by a 532 nm laser in the ambient air was effective in removing the carbon precipitates; in the case of ITO, no trace of carbon could be observed in the Raman spectra following irradiation. The combination of vacuum annealing and laser irradiation could provide a practical means for reducing carbon impurities in thin films.
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- Award ID(s):
- 2335744
- PAR ID:
- 10578635
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology B
- Volume:
- 43
- Issue:
- 2
- ISSN:
- 2166-2746
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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